Field
Embodiments of the present invention generally relate to a positioning and shape modifying system for supporting an exchangeable object, and more particularly to a positioning and shape modifying system for a patterning device of a lithographic apparatus.
Background Art
A lithographic apparatus is a machine that applies a desired pattern onto a substrate, usually onto a target portion of the substrate. A lithographic apparatus can be used, for example, in the manufacture of integrated circuits (ICs). In such a case, a patterning device, for example, a mask or a reticle, may be used to generate a circuit pattern to be formed on an individual layer of the IC. This pattern can be transferred onto a target portion (for example, including part of, one, or several dies) on a substrate (for example, a silicon wafer). Transfer of the pattern is typically via imaging onto a layer of radiation-sensitive material (resist) provided on the substrate. Generally, a single substrate will contain a network of adjacent target portions that are successively patterned. Conventional lithographic apparatuses include so-called steppers, in which each target portion is irradiated by exposing an entire pattern onto the target portion at once, and so-called scanners, in which each target portion is irradiated by scanning the pattern through a radiation beam in a given direction (the “scanning”-direction) while synchronously scanning the substrate parallel or anti-parallel to this direction. It is also possible to transfer the pattern from the patterning device to the substrate by imprinting the pattern onto the substrate.
The manufacture of ICs and other devices with a lithographic apparatus generally involves the replication of extremely fine sub-micron patterns. Accordingly, these patterns require accurately positioning and shaping the movable components of the lithographic apparatus, for example, a substrate or a patterning device.